I've heard many different things about how this debuff works on an enemy target. I've read that the DoT is based on the initial hit, and all consecutive (relevant) strikes extend the duration of the damage the initial hit would've caused(1). I've read that a Shred/Mangle after the initial strike will reapply a new DoT based on that ability's damage(2). I've also read that the DoT rolls every time a new Shred/Mangle is done(3).

How it's supposed to work: Every hit of mangle/shred/maul leaves a 4 second dot that ticks every 2 seconds. The dot is unaffected by haste and cant crit, and is unaffected by anything that increases magical damage, like curse of elements. The total damage of the dot is 10% of the mangle/shred/maul that caused it, so 5% per tick.

If there was already a Fiery Claws dot on the target, damage left on that dot gets added to the new one.

It's a bit buggy at times tho, and does less damage than you would expect it to do:

When Fiery Claws got refreshed the first time, there was still a 838 damage tick left on the old Fiery Claws. With a 31.5k crit and a 16.5k hit, you would expect the next 2 ticks to do a total of 3.15+1.65+0.8 = 5.6k damage, or 2.8k damage per tick. But the observed damage was only 2.2k per tick

Ah, I see. So the damage is supposed to roll (though live seems to exhibit some formula otherwise).

I ran 3 more tests and confirmed the math just to be sure I understood what was going on and as you mentioned, there doesn't seem to be any real correspondence between one set of numbers and the next (beyond the first or second Shred, which usually seems to be exactly 10%). Here is one of the sets of results.

It seems that Fiery Claws is incapable of including damage from three Shreds, resulting in skewed data for the rest of the "set" (meaning, until Fiery Claws falls off). I had a result showing something like:

Shred: 16000Shred: 18000FC: 800Shred: 17000FC: 1750

The second Fiery Claws damage should be 800+(1800/2)+(1700/2)=2550, however Fiery Claws only included damage from most recent two Shreds.

TL;DR: Hope Blizzard fixes 2piece.

[Edit 7.26] The above "code" combat text is from entering combat to leaving combat, though after running another test yesterday (and after seeing some additions to this thread), I found that "expected" FC damage and "actual" FC damage is relatively the same -- the margin of difference is not nearly what it was, consistently, given any random factors.

Last edited by Reverie on Tue Jul 26, 2011 5:01 pm, edited 1 time in total.

Yes, it's rolling, so bonus damage from last mangle/shred is added to the remaining bonus damage of the any current DoT. Also note that duration seems to be extended to 6s in that case, and damage is split over 3 ticks instead of 2.

Reverie, it looks like your combatlog snippet was not the start of the fight and a DoT had already been applied - I mean, even the very first tick does not make any sense, while in my own combatlogs it's always tracing back to exactly 10% bonus damage.

From my experiments I can say that the 2T12 bonus is working a lot better than advertised. Actually, I've never seen it do less damage than it was supposed to do.

Aura Lag is the time it takes a buff/debuff application to get to the server and be applied. SimulationCraft and Mew use 150 ms by default.

Fiery Claws has a "damage pool". As in, each refresh adds to "saved damage", so refreshing it in theory causes 0 losses.

Fiery Claws will "much". If you have 2 applications that are near simultaneous, you will lose one of the applications. This does not happen with kitties because applications are throttled by the GCD, and aura lag is usually < 1.0 sec, and none of the abilities have travel time, but it will happen for Bears because of Maul. This is a bug, and it hurts DPS when it happens.

Fiery Claws will "roll". If you have an application occur near simultaneously to when a tick will occur, it will not deplete the damage pool, essentially gaining a free tick. (Naming taken from the infamous Rolling Ignite behavior back in vanilla). This is a bug, and it helps DPS when it happens.

Both of those two bugs are race conditions and make perfect sense given the logical structure of the server side code.

Crossbow wrote:I made a small addon that tracks it all in real-time, and had a short test on the dummy:

01:52:45 FieryClawsTracker: + Shred: 25011 <-- This shred is actually applied to the Fiery Claws debuff at this point01:52:45 FieryClawsTracker: - Fiery Claws: 1067 <-- But this tick still got off, so can be considered as bonus

This log is a illustration of rolling, although without a full combat log, the timing granularity of the output is insufficient for me to say so for sure. I would assume that the Shred and Tick are within ~150 ms or so.

Now supposedly, Ignite/Deep Wounds have broken refresh mechanics that also cause you to lose procs (and this is how both SimulationCraft and Mew) will model Fiery Claws but I have not seen any conclusive proof that this occurs. Specifically the behavior I'm looking for is "If Fiery Claws is refreshed while the existing debuff duration is > 4.0 sec, you will lose the refresh". If people consistently are reporting high values, it's rather likely that this bug does not apply to Fiery Claws but I would need to see multiple combat logs with millisecond resolution before I would change the code.

Looks like this can be attributed to the delay between the shred/mangle hitting, and the dot refreshing; this seems to take about 0.6-0.75sec in most cases. Any FC ticks falling in this period will be bonus ticks.

Mihir wrote:Looks like this can be attributed to the delay between the shred/mangle hitting, and the dot refreshing; this seems to take about 0.6-0.75sec in most cases. Any FC ticks falling in this period will be bonus ticks.

It's dependent on client latency and a host of other factors, but yes, that's what happens. As I said, it's a race condition.

Mihir wrote:As far as i could see we don't suffer from losing procs due to broken refresh mechanics, for example from yesterday's raid:

<logs snipped>

At the end i do 2 shreds without a tick, but the calculated damage in the end is still correct.

Ignite only really bugged out (at least recently) when multiple things that would proc it happened at the same time. This was an issue because fireball has a travel time, scorch doesn't, and fire has dots. So they could potentially have a scorch, a fireball, and a dot tick or two happen within the same millisecond, and the server register only the ignite from the dot tick. Recently blizz removed the ability for dots to proc ignite, which I imagine has largely fixed the issue, though I don't really keep up to date on Mage mechanics other than reading patch notes.

When you consider that, it's not surprising that we don't have any issues with munching because the closest we can have 2 shreds together is 1 second. However it can turn up for bears with maul being off the global doing a mangle and a maul simultaneously, but I doubt it's really a huge deal.